<template>
  <div class="star" :class="starType">
    <span v-for="itemClass in itemClasses" :class="itemClass" class="star-item"  track-by="$index" ></span>
  </div>
</template>
<script>
const LENGTH = 5
const CLS_ON = 'on'
const CLS_HALF = 'half'
const CLS_OFF = 'off'

export default {
  props: {
    size: {
      type: Number
    },
    score: {
      type: Number
    }
  },
  // 计算属性
  computed: {
    starType () {
      return 'star-' + this.size
    },
    itemClasses () {
      let result = []
      let score = Math.floor(this.score * 2) / 2  //   .5处理
      let hasDecimal = score % 1 !== 0  // 看有没有小数
      let intege = Math.floor(score)
      for (let i = 0; i < intege; i++) {
        result.push(CLS_ON)
      }
      if (hasDecimal) {
        result.push(CLS_HALF)
      }
      while (result.length < LENGTH) {
        result.push(CLS_OFF)
      }
      return result
    }
  }

}
</script>
<style lang="stylus" rel="stylesheet/stylus">
@import '../../common/styls/mixin.styl';

.star 
  font-size: 0;
  .star-item 
    display: inline-block;
    background-repeat: no-repeat;
  &.star-48 
    .star-item 
      width: 20px;
      height: 20px;
      margin-right: 22px;
      background-size: 20px 20px;
      &:last-child 
        margin-right: 0;
      &.on 
        bg-image('star48_on');
      &.half 
        bg-image('star48_half');
      &.off 
        bg-image('star48_off');
  &.star-36 
    .star-item 
      width: 15px;
      height: 15px;
      margin-right: 6px;
      background-size: 15px 15px;
      &:last-child 
        margin-right: 0;
      &.on 
        bg-image('star36_on');
      &.half 
        bg-image('star36_half');
      &.off 
        bg-image('star36_off');
  &.star-24 
    .star-item 
      width: 10px;
      height: 10px;
      margin-right: 3px;
      background-size: 10px 10px;
      &:last-child 
        margin-right: 0;
      &.on 
        bg-image('star24_on');
      &.half 
        bg-image('star24_half');
      &.off 
        bg-image('star24_off');
      
    
  

</style>